quote:In addition to Obama and Bloomberg, prosecutors say Richardson also sent a letter laced with the poison to Mark Glaze in Washington. Glaze is the director of Mayors Against Illegal Guns, a group co-founded by Bloomberg.

quote:Ricin, is a natural, highly toxic compound that is extracted from castor beans. It has been used experimentally to kill cancer cells, according the Center for Disease Control and Prevention in Atlanta. It is a potentially fatal if ingested or inhaled.